Aquaculture – the production of fish and other aquatic livestock in a hatchery system – seems to have created mixed perceptions depending on who you talk to, where you live, and what you read. Most folks believe that wild is better. As I type this, “Iron Chef” is on the boob tube and famous chef Bobby Flay is gushing over the wonder of “wild” striped bass. Striped bass is a migratory fish native to the eastern coast of North American. It spawns in rivers and spends adulthood in the brine. This fish grows to enormous size; the flesh is meaty and extremely versatile. It also was almost extirpated by overfishing. Luckily, effective management coupled with habitat improvement has made this one of the success stories for restoration of a fish stock. Good news. Unfortunately, this is a rare example. Lots of fish stocks around the world are stressed and need more care for a variety of reasons.
Statistics compiled by the Food and Agriculture Organization of the United Nations show that the production of wild fish and other sea life has topped out at roughly 100 million metric tons per year. During the past couple of decades the production of aquaculture has steadily climbed. This is no coincidence. The globe’s human population has doubled in the past 40 years and these new people want protein. We may think that chicken and beef are the primary protein sources that people want via our American perspective. We’re wrong. Most of the world wants fish.
The mixed perception of aquaculture is largely region-specific . In Asia, fish have been cultured for thousands of years – the connection between the fish produced in ponds and their wild source is celebrated. Aquaculture receives no ill will and is perceived as complementary to the gifts of nature. In the United States and Canada, environmentalists and aquaculture have experienced some friction. In the 1800s, when fish hatcheries were springing up throughout the continent, the European common carp was the common product. These were stocked widely throughout the country and are now considered to be a terrible invasive species. Another fish, the rainbow trout native to the western coast of the US has been stocked widely throughout the eastern US, again causing problems. More recently, well-intentioned attempts to use hatchery-reared surrogates to replace declining fish stocks has led to problems. In the Pacific northwest of North America, hatchery-reared salmon just don’t make up for the loss of naturally produced counterparts stymied by dams, habitat degradation, overfishing, and changing climate. Mistakes happen. But we learn from them and can improve our approaches. In our Center, geneticists are working with hatcheries to produce stocks of sturgeon with integrity. Similar approaches are being adopted throughout North America to improve declining fish populations. It is imperative that population geneticists, policy makers, and managers learn to speak in the same language and communicate effectively to maintain genetic diversity.
So, misperceptions about aquaculture are largely driven by environmental issues. However, aquaculture has another mission – producing tasty food efficiently and safely. In fact, aquaculture, if done correctly, can reduce fishing pressure on stressed wild stocks. Take, for example, Bobby Flay’s wild striped bass. Striped bass are great, but access to them from the waters of the Atlantic Ocean is limited due to regulations and cost. An alternative – the hybrid striped bass or sunshine bass – is produced in hatcheries both out east as well as in my backyard in Illinois. The complex life history and large body size of striped bass make them difficult to maintain in the limited space of a hatchery system. The solution is to mate them with their smaller close relative, the white bass. The resulting fish grows quickly, tastes wonderful, and thrives in the hatchery environment. I have seen several cooking shows where the “striped bass” being prepared are actually hybrids. Hybrid striped bass take the stress off the wild striped bass by creating a consistent, controlled supply that is disconnected from the wild fishery. The wild fishery can do what it does best, support a robust recreational and charter industry without worrying about huge commercial pressure from restaurants and groceries. Aquaculture takes the uncertainty out of the fish supply by maximizing the young produced by the adults. It may take thousands of adults spawning in the wild to ensure that one fingerling survives to the next generation. In a hatchery, a pair of adults may produce thousands of young that will reliably make it to the table. That’s efficient production at its finest.
I’m oversimplifying here. There are many complex issues. Hatchery fish can escape back into the wild and challenge the genetic integrity of parent stocks. Diseases crop up in the crowded hatcheries. Pressure is always there to raise non-native fish that may escape into the wild and become invaders. High densities of fish may compromise water quality. But, with good management, education, and sound regulations all of these issues can be rectified. I am confident that aquaculture will be one of the many ways we will curtail hunger as human populations rise in the 21st century. Our Center is ready to meet the challenge.